AMTIC - Ambient Monitoring Archive for HAPs

In November 2024, the EPA published the 2022 Ambient Monitoring Archive (AMA) for the  Hazardous Air Pollutants (HAPs) (i.e., "the Archive") that houses over 115 million data records from over 6,000 monitoring sites from 1990 through 2022. Data come from EPA's Air Quality System, the Texas Commission on Environmental Quality, the South Coast Air Quality Management District, the National Atmospheric Deposition Program, the National Oceanic and Atmospheric Administration, and the Massachusetts Institute of Technology,  other state, local, tribal, and federal monitoring agencies, and other academic, community, and short-term studies. Due to the size of the 2022 Archive, the Microsoft Access data files are divided by state and year; the .txt and .Rda files (generated by the R programming language) are presented by year.

Ambient Monitoring HAPs Data By Year

The 2022 Archive for HAPs data from 1990 to 2022 are presented by year in zipped Microsoft Access databases and .txt files. Please note that file sizes range from 5.67 MB to 492 MB.

Year	Year	Year	Year
			2022          (476 MB)
2021           (492 MB)	2020         (225 MB)	2019       (211 MB)	2018         (198 MB)
2017         (211 MB)	2016         (261 MB)	2015        (253 MB)	2014         (264 MB)
2013         (240 MB)	2012         (224 MB)	2011         (206 MB)	2010          (194 MB)
2009         (188 MB)	2008         (172 MB)	2007         (176 MB)	2006         (168 MB)
2005         (172 MB)	2004                 (149 MB)	2003                (127 MB)	2002         (111 MB)
2001         (107 MB)	2000                 (90.1 MB)	1999         (80.4 MB)	1998                (73.8 MB)
1997         (61.9 MB)	1996         (51.0 MB)	1995         (36.8 MB)	1994         (20.9 MB)
1993         (11.8 MB)	1992         (8.44 MB)	1991         (6.99 MB)	1990         (5.67 MB)

Air Monitoring HAPs Data By State

Files are also available from 1990 to 2022 by state, the District of Columbia, Puerto Rico, and the Virgin Islands in zipped Microsoft Access databases. Please note that file sizes range from 848 KB to 646 MB.

State	State	State	State
Alabama (9.73 MB)	Alaska  (24.3 MB)	Arizona (19.3 MB)	Arkansas  (2.25 MB)
California (485 MB)	Colorado  (54.2 MB)	Connecticut  (32.5 MB)	Delaware  (7.22MB)
District of Columbia  (20.3 MB)	Florida (22.2 MB)	Georgia (52.5 MB)	Hawaii (22.8 MB)
Idaho (3.47 MB)	Illinois (39.2 MB)	Indiana (70.3 MB)	Iowa (5.10 MB)
Kansas (5.19MB)	Kentucky (16.9 MB)	Louisiana (39.0 MB)	Maine (46.6 MB)
Maryland (40.1 MB)	Massachusetts (52.9 MB)	Michigan (44.6 MB)	Minnesota (35.5 MB)
Mississippi  (9.33 MB)	Missouri (25.3 MB)	Montana (7.49 MB)	Nebraska (2.04 MB)
Nevada (4.07 MB)	New Hampshire (27.4 MB)	New Jersey (42.6 MB)	New Mexico (7.52 MB)
New York (64.5 MB)	North Carolina (16.8 MB)	North Dakota (2.77 MB)	Ohio (22.0 MB)
Oklahoma (14.0 MB)	Oregon (21.9 MB)	Pennsylvania  (46.1 MB)	Puerto Rico (0.99 MB)
Rhode Island (24.4 MB)	South Carolina (14.4 MB)	South Dakota (3.78 MB)	Tennessee (5.40 MB)
Texas (1 of 2) (646 MB) Texas (2 of 2)  (634 MB)	Utah (17.2 MB)	Vermont (20.4 MB)	Virgin Islands (848 KB)
Virginia (18.2 MB)	Washington (17.6)	West Virginia  (4.25 MB)	Wisconsin (104 MB)
Wyoming (4.75 MB)

All 2022 Archive Monitoring Data and Annual Data Summaries

• All .Rda data files by year (ZIP) (828 MB) contains all data in the 2022 Archive presented by year in .Rda files (generated by the R programming language).
• Annual Statistics (XLSX) (193 MB) provides annual statistics by pollutant, site, sampling duration, and year and supporting information assisting in trends analysis.

Supporting Files for the 2022 Archive

• Field Descriptions (PDF) (1 page, 32.8 KB) describes the fields in the 2022 Archive files.

• Data Dictionary (ZIP) (12.4 MB) contains ten data dictionaries needed for describing and standardizing the raw data and are recommended for providing additional context to the concentration records. Data dictionaries are initially retrieved from EPA's AQS website with additional data elements added.
• Supporting appendices (ZIP) (132 MB) contains six supporting appendices including information regarding overlapping records, invalidated records, sampling frequency code corrections, questionable values, negative concentrations, and program rankings.
• Lookup Tables (XLSX) (218 KB) contains additional cross-referenced information in the annual statistics excel file, field descriptions in the annual statistics excel file, R code used to calculate the annual statistics, and other descriptive information. 

Supporting Documentation for the 2022 Archive

• Technical Report (55 pages, 1.02 MB)  provides background information, describes data sources, and documents the improvements, modifications, and additional data incorporated into the development of the 2022 Archive.
• Annual Statistics Documentation (PDF) (10 pages, 434 KB) documents the steps used to calculate the annual statistics along with descriptors of the corresponding R code, the quality assurance methodology and results, and answers to frequent questions.